build(deps): bump tokio from 0.2.21 to 0.2.22

Bumps [tokio](https://github.com/tokio-rs/tokio) from 0.2.21 to 0.2.22.
- [Release notes](https://github.com/tokio-rs/tokio/releases)
- [Commits](https://github.com/tokio-rs/tokio/compare/tokio-0.2.21...tokio-0.2.22)

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -2077,9 +2077,9 @@ dependencies = [
 
 [[package]]
 name = "tokio"
-version = "0.2.21"
+version = "0.2.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d099fa27b9702bed751524694adbe393e18b36b204da91eb1cbbbbb4a5ee2d58"
+checksum = "5d34ca54d84bf2b5b4d7d31e901a8464f7b60ac145a284fba25ceb801f2ddccd"
 dependencies = [
  "bytes",
  "fnv",

zebra-state/Cargo.toml

@@ -17,7 +17,7 @@ sled = "0.33.0"
 serde = { version = "1", features = ["serde_derive"] }
 
 [dev-dependencies]
-tokio = { version = "0.2.21", features = ["full"] }
+tokio = { version = "0.2.22", features = ["full"] }
 zebra-test = { path = "../zebra-test/" }
 spandoc = "0.2"
 tracing = "0.1.16"